1. Field of Invention
The present invention relates to an amorphous magnesium alloy having improved specific strength and ductility, and to a method for producing the same.
2. Description of Related Arts
Magnesium alloys have tensile strength of approximately 24 kg/mm.sup.2 and specific gravity of 1.8, as is stipulated in JIS H5203, MC2. Magnesium alloys have therefore a high specific strength and are promising materials to reduce weight of automotive vehicles, which weight reduction is required for conserving fuel consumption.
Japanese Unexamined Patent Publication No. 3-10141 proposes an amorphous magnesium alloy having a composition of Mg-rare earth element-transition element. The proposed amorphous magnesium alloy has a high strength; however, since a large amount of the rare-earth element is added to vitrify the Mg alloy, enhancement of the specific strength is less than expected. The proposed Mg alloy would therefore not be as competitive as other high specific strength materials.
It is also known that the ternary Mg-Al-Ag magnesium alloy can be vitrified. The Mg-Al-Ag amorphous alloy has a low crystallization temperature and has the disadvantage of embrittlement when exposed at room temperature in ambient atmosphere for approximately 24 hours.
The Mg-rare earth element-transition metal alloy has a higher specific weight than the Mg-Al-Ag alloy and hence does not have a satisfactorily high specific strength. In addition, since several compositions of the Mg-rare earth o element-transition metal alloy embrittle when exposed as described above, the properties of this alloy are unstable. Under the circumstances described above, development of the practical application of Mg alloys has lagged behind Al alloys.